Pressure differential connection for meters



Fill 23, 1935.. M1,- M. BORDEN ET AL.

PRESSURE DIFFERENTIAL CONNECTION FOR METERS Filed April 5, 1932 \w M N Q\ NN Q\ .0 ,Q & m-. m 1-1 J 5 Patented Apr. 23, 1935 PRESSURE DIFFERENTEAD CONNECTION FORNIETERS Moro Borden, Philadelphia, Pa, and Allen sweeten, Pitman, N.- J., assignorstoSimplex, Valve .&;vMeter. Company, Philadelphia, Pa, a corporation of Delaware Application: April 1932;\Serial No.' 603,434

12 Claims.

Thisainventiorr irelates torconnections between meterssandzconduits or casingszcontaining a moving-efluid; andinx which the: pressure:- difierential results :fr'onrsuch movements; and more' particu larlmto: a means enabling: accurate adaptation of a standardxmeteratozsuch conduits orcasings- It:

ofterrzhappenss that :aft'er: installation of a conduitxitxbecomes :necessarywto. change the meter employediirriconnectiontherewith: or to apply a *meter thereto; theiformer': ordinarily resulting from. aschange oftflow-:. inzthe:=conduit; Forqex ample, flow linesacontaining venturi oiten have theniowamcreasedstherein torsuch an vextent that thezfiowis not proportionate. to: the: installed venl5'" turi-andnsincea thiszwill rrender th'e venturi inaccurateiirrz connection-x. with 1. tliewmeter for which it; was :originallyrdesigned; .a new=:meter must 1 besuppliedzor;anproperly proportioned venturi inserted. Since insertion of a newssventuri would :4 meanrxcuttingizofiitheaflow; often aniimpossib'ility, the useszoisa nevw'meterjs generally resorted-to; Under: such;circumstances .-it is the practice to conduitacontaining: a-zventurintubepr its-equivalent device.- iszirmeasured; prefierablysby a: U a tube witlrits balancingtliquid. When suchnisconriected-toathe regular zmainzcandrthroat sections of a Venturi :tube": or toctl i'e;-;proper::connections on either z-side'rofzan orifice, vaccurate acalculaLtions of theerate ofzidischargei mayrbes basedupon the resulting; deflections-s of theeabalancing liquidin the Uetube. Itisshowever,"necessaryiin connect ingiwthee meter" to aspeciallyrdesign' the. meter and meter chart, for such taps are located ap-proxi mately and 1 one: cannot :provideaconnections givings pressures": exactly suitable to a standard meter-"without experimental work: in their" relocation; Fastandardymeter signifies a measuring gdevice::accommodatingzzonlyx a certain maximumepressuresdifferential; andiwhich: would not be accurately operative if subjectedito greater pressure differentials.

' An; important object:of the present invention is:toaprovideiconnection-apparatussfor use in .con-

junction with"; overloaded: venturi; 1 orwith' .ven-

1 turi assoriginally installed wherezthereis a probability of suclr'zoverloading' which:connection is of such character".-tliat= ar suitable differential presuses ofravstandard meter; 0 D) A1 furthen-and more 'specific object of the-in vention is the provision of :an arrangement such that the effective positionofo-neof the tapopenings maybe adjustably' variedso that an accurate accommodation to a standard meter which'has beenprovided with flow scales; chart or meansfor totalizing the flow, designed upon :the basis of assumed exact" relations of f pressure difieren tial to flow maybe had-"and this accommodation may'sbe substantially :varied'if demands upon the flow line with whichthe meter'vis being employed vary and the pressures at the connections vary as a result thereof so that the'meterbecomes inaccurate or of insuflicient capacity;

Afurther object ofthe'inventionis. the provision-of a-connection whiclrmaysbe employed to accurately adapt" a standard meter without the exercise-0f "skill or experimentation and' which can be employed" in' practically any situation where a-pressure differential exists in a: conduit or casing."

Theseand other objects-we attain "by-the construction shown inthe accompanying drawing wherein; for the purpose of illustratiom we have shown a" preferred embodiment of our I invention and wherein Fig; 1 is a side elevation-of a venturi having a" meter connected therewith in accordance with our invention; and

Fig. 2"is a longitudinal sectional viewthrough the adjustable'connection'.

Referring now more particularly 'to the drawing, the numeral H] generally designates the downstream end of a standard venturi; ll, 12;

I3; I l and Hi; taps through the wall-of the venturi and spaced longitudinally of such downstream end. As iswell known to those familiar with the art the pressures derived at such taps increase with the reces'sionof the tap from the Venturi throat l6. Due, however, to internal conditions attending flow as turbulence; it isimpossible to accurately compute the pressures derived from anyof' the taps, particularly those near the throat, sothat when the taps are-made it is not known with suflicientexactness for operationof standard meters how much the pressure at the tap l-will be less-'thanthat at the tap I2; and that at-the tap I2 lessthan that atthe tap l3; and so forth; Standardmeters such as that generally-designatedat M are, of course, designed to operate withthe delivery of fixed pressure differentials under certain fixed flow rates:

In" accordancewith the present invention, one terminal ofthismeter is connected "to a fixed tap taken -from-the"venturiwhich maybe any 'oneof the taps II to J5 or a further tap l1 taken for example at the throat of the venturi. The differential between the selected tap, at present shown as the tap I5, and any of the remaining taps I I, I2, I3 and I4, will probably 'fail to provide an accurate tap for the second connection for the standard meter. However, the pressure necessary for the second meter connection, in order that proper differential may be had, will be positively indicated as lying between two of the remaining taps, as for example, and as in the present showing, between the taps I I and I2. The taps I I and I2 are then connected by a pipe I8 extending longitudinally of the venturi, the ends of the pipe communicating with the taps while the central portion of the pipe has extending longitudinally therethrough a longitudinally shiftable tube I 9 having an opening 20 formed therein communicating with the interior of the pipe and having one end thereof closed as at 2! and the opposite end thereof adapted for an outlet to a meter connection at 22. This tube extends through packing glands 23 at the end walls of the central section of pipe I8 andhas associated therewith a locking means 24 whereby it may be locked in adjusted positions. The looking means 24 is at present shown as comprising a tapered split sleeve 25 mounted in a bracket 28 carried by one of the end portions of the pipe I8 and having the tube I9 passed therethrough. By loosening the sleeve in its mounting in the bracket, the tube I9 is released and may be shifted to a new position:

It will be apparent that the pressure at the tap I2 will be greater, because of its relatively lower velocity, than that at the tap II Where the cross sectional area is smaller and the velocity higher. A small fluid flow will, therefore, take place from the connection I2 through the pipe I8, past the opening 20 and through the connection II into the Venturi tube or main. Furthermore, it will be seen that the pressures between the taps I2 and II will have different intensity at different points in this auxiliary conduit, composed of the taps I2 and II, the pipes 21 and I8, the highest pressure value being adjacent to I2 and the lowest at the outlet II. I

It will be obvious that by longitudinally shifting this tube the opening 29 may be placed so that the desired intermediate pressure between the pressures delivered at the taps II and I2 is obtained and, accordingly, adjustment of this tube will provide an accurate pressure differential with the second tap to which the standard meter is connected. Obviously, if the flow rate through the venturi is varied at any time to an extent destroying the exact pressure differential thus obtained, the tube I9 may be again adjusted to correct the error by the means described. While we have shown an excess of taps as having been made in the venturi beyond those which are actually employed in meter connections, it will be understood that with knowledge of the flow rate and size of the venturi it will be readily possible to compute the relative positions of taps such as taps II, I2, and I5 so that with the meter connection at the tap I5 the proper pressure differential will be obtained by the taps I I and I2, thus eliminating the necessity for the formation of the additional taps I3 and I4.

While we have above described the connections as having been made at the downstream end of the venturi, it is to be understood that this is merely a description of a, preferred lo-- cation for, obviously, taps could be made at any di1ferentials-operated meter associated therewith, a fixed tap, in the venturi and connected with one terminal of said meter, an elongated pipe, connections between said pipe and the venturi providing different pressures at opposite ends of the pipe, an outlet for said pipe micrometrically adjustable longitudinally of the pipe and a connection between the second terminal. of the meter and said adjustable outlet.

-2. In combination with a venturi, a meter operated by pressure differentials associated therewith, a'connection between one terminal of the meter and a fixed tap in the venturi, a conduit communicating with the venturi at longitudinally spaced points and including a section extending longitudinally of the venturi and lying: between said points, a tube adjustable longitudinally of said section and having an opening within said the second terminal of said meter. 3. An adjustable tap for venturis comprisin a conduit extending longitudinally of the venturi and having its ends communicating with the venturi at points spaced longitudinally thereof, and a tube adjustable longitudinally of said 1 conduit and having an opening communicating with said conduit.

4. In combination with a venturi, a meter operated by pressure differentials associated therewith, a connection between one terminal 30. section and av connection between saidtube and of the meter and a fixed tap in the venturi, a

conduit paralleling the axis of the venturi communicating with the venturi 'at longitudinally spaced. points, a tube adjustable longitudinally of said conduit and having an opening within said conduit and a connection between said tube and the second terminal of said meter.

5. In combination with a venturi, a meter operated by pressure differentials associated therewith, a connection between one terminal of the meter and a fixed tap in the venturi, a conduit communicating with the venturi at longitudinally spaced points, and a connection between the conduit and the second terminal of the meter adjustable longitudinally of the conduit.

6. An adjustable tap for venturis comprising a conduit having its ends communicating with the venturi at points spaced longitudinally thereof, a tube adjustable longitudinally of said conduit and having an opening communicating with 1 said conduitjand means for locking the tube in 1 adjusted positions.

7. In combination with a conduit containing a moving fluid, a pair of taps communicating with the conduit atpoints of different pressure therein, an outlet and a connection in communication with both said taps and with said out let along which said outlet is adjustable to determine the point of communication with the connection.

8. An adjustable tap for conduits comprising a duct communicating with theconduit at points of different pressure in the conduit and an outlet for said duct adjustable longitudinally of the duct.

9. An adjustable tap for conduits comprising a duct communicating with the conduit at points of difierent pressure in the conduit, an outlet for said duct adjustable longitudinally of the duct, and means for locking said outlet in adjusted positions.

10. In combination with a conduit and means producing pressure difierentials in a moving fluid in the conduit, a meter operated by pressure differentials associated with the conduit, a connection between one terminal of the meter and a fixed tap in the conduit, a duct communicating with the conduit at points therein having difierent pressures resulting from said means, an outlet for said duct adjustable longitudinally of the duct and a connection between said outlet and the second terminal of the meter.

11. The combination with a conduit and a pressure-differentia1-operated meter associated therewith, of a fixed tap in the conduit connected with one terminal of the meter, a pipe, connections between opposite ends of the pipe and a conduit providingdifierent pressures at opposite ends of the pipe, an outlet for the pipe adjustable longitudinally of the pipe and a connection between the outlet and a second terminal of the meter.

12. In combination with a venturi, a pressure-differentials-operated meter associated therewith, a fixed tap in the venturi and connected to one terminal of the meter, an exteriorly disposed conduit connecting points of difierent pressure in the venturi whereby there is a continual flow through said conduit, an outlet adjustable longitudinally of said conduit and a connection between the second terminal of the meter and said adjustable outlet.

MORO M. BORDEN. ALLEN W. SWEETEN. 

